DVB Inspector

User manual

Tree view - PIDs

This section of the Tree is only shown when the option "PSI only" in the Tree View menu is NOT enabled.

In this section each PID is represented, independent of the PSI information. That means some PIDs that are not present in the PSI are still shown.

For ease of recognition each PID gets assigned a name, based on the PSI information. This can look something like 'Video MPEG2 - Nederland 1'. From the PSI it is concluded this PID contains the video for service 'Nederland 1'.

Transport packets

TS packets for PID
Under Transport packets the TS packets for this PID are grouped together. See the section on TS Packets for more details.

PSI Data

PSI data can be shown as raw tables, without interpretation. This is enabled in the settings menu. This may assist in analyzing some private tables (like Conditional Access tables). Sometimes a PID appears to contain PSI data, but not a valid table structure. For some types of private data this may result in a lot of 'false' tables, which can use a lot of memory. Then it can help to disable Generic PSI parsing.

warning generic PSI not enabled

After enabling generic PSI the section will be displayed like this:
generic PSI enabled

Interpret as PSI

Sometimes unknown PSI tables are present on 'strange' PIDs. These may be used for when the signal is retransmitted on a different network to replace the original PSI. In this example info is present on PID 3218;
unknown PSI
The table_ids match that of EIT, but it is not on PID 18. So it will not show up in the PSI section of the Tree view.

DVB Inspector can be forced to interpret PSI data, based on just the table_id by selecting 'Interpret as PSI'.
Interpret as PSI
The result will show the PSI as if it was normal part of this stream.
Interpret as EIT

PES Data


For PES data the stream_id is used as indicator what type of data we are dealing with. When the data is not encrypted some more general information is shown.


Some types are (partially) supported for detailed inspection. To use this, select the PID to be inspected, right click, and select 'parse data' from the popup menu. This will take a few seconds while DVB inspector rescans the file. Then an extra sub folder 'PES Data' will be added to the PID. Supported data types are MPEG2 Video,H.264 Video, H.265 Video, H.266 Video, MPEG2 Audio, AC3 & E-AC3 (Dolby) Audio, AAC Audio, EBU Data (Teletext, VPS and WSS), DVB subtitles and Timed Text Markup Language (TTML) subtitling.

Although T2MI data is not PES data, parsing it is supported by DVB Inspector.

Video MPEG2 (ISO 13818-2 / H.262)

MPEG2 Video
Above an example of a MPEG2 video stream. This stream has one frame per PES Packet, sometimes streams have an entire Group Of Pictures per PES packet (see below), or even one single section.

Frame structure

MPEG2 Video Frame Structure
When the "PES Data" node is selected for a MPEG2 video stream the right panel will show a graph with the size and transmission order of the different frame types (IBP).

Preview

MPEG2 Video Preview
When a PES packet is selected which contains an I-Frame (or of Group Of Pictures containing an I-Frame) a preview of the I-Frame will be shown in the right panel. This preview has the same dimension in pixels as the MPEG-frame, so aspect-ratio information is ignored.

Sequence header of Group Of Pictures

Video H.264

pes video h264
Above an example of the structure of a H.264 (or ISO/IEC 14496-2) video stream.

Frame structure

H.264 Video Frame Structure
When the "PES Data" node is selected for a h.264 video stream the right panel will show a graph with the size and transmission order of the different Access Units (incl. Filler Data).

Multi View Coding (MVC)

pes h264 mvc video
This is an example of a MVC (Multi View Coding) H.264 video stream. This is used for 3D video. It can be found in .ssif files on a Blu-ray disc.

Video H.265 (HEVC)

pes video h265
Above an example of the structure of a High efficiency video coding (HEVC), or H.265 /ISO/IEC 23008-2 video stream.

Frame structure

H.265 Video Frame Structure
When the "PES Data" node is selected for a h.265 video stream the right panel will show a graph with the size and transmission order of the different Access Units (incl. Filler Data).

Video H.266 (VVC)

pes video h266
Above an example of the structure of a Versatile video coding (VVC), or H.266 video stream.

Frame structure

H.266 Video Frame Structure
When the "PES Data" node is selected for a h.266 video stream the right panel will show a graph with the size and transmission order of the different Access Units (incl. Filler Data).

Audio MPEG

MPEG Audio
Example of the audio packets for TV service Nederland 1.

Graph

Graph view of the audio wave form
When the "PES Data" node is selected for audio MPEG stream the right panel will show a graph of the audio wave form.

Play audio

Play audio menu item
When the right mouse button is clicked while the "PES Data" node is selected, the audio will start playing.


Stop audio menu itemWhile the audio is playing the menu item will change to stop.

RDS via UECP

For audio streams where a ancillary_data_descriptor in the PMT indicates the presence of "RDS via UECP" data the UECP data is shown.
RDS via UECP

Audio AC3 & E-AC3

AC3 Syncframe
Above an example of a AC-3 audio stream. AC-3 streams are recognized when they are indicated by a AC-3 descriptor in the PMT (as described for DVB), or by a registration descriptor with value "AC-3" (as described for ATSC)

Audio AAC (ISO/IEC 14496-3 Audio with the LATM transport syntax)

AAC parsing
Example of AAC Parsing. Detection of Spectral band replication (SBR) as used in HE-AAC is not yet supported.

Audio Dolby AC-4 ()

AC-4 Syncframe
Above an example of a Dolby AC-4 audio stream. AC-4 streams are recognized when they are indicated by a AC-4 extension descriptor in the PMT

EBU Data / Teletext / VPS / WSS

This shows data for PIDs that contain Vertical Blanking Information (VBI) according to EN 301 775. For streams of type 'private_stream_1', and the first byte of the PES packet (data_identifier) is between 0x10 to 0x1F or 0x99 to 0x9B. Be carefull, sometimes other private data is wrongly interpreted as EBU data, so the displayed information will be meaningless.

Sometimes teletext, VPS and WSS information is transmitted within a single PID, sometimes different PIDs are used.

In this section first the PES packets are shown in the order of transmission (the "RAW" data), then the interpretation of the EBU data is shown for teletext, VPS and WSS data.

Teletext

Remember this is not a teletext decoder for viewing pages as they should be presented, but an analyzer, to show the logical structure of the data. For the details of teletext see EN 300 706.

Teletext
A teletext service is organized into 8 magazines, numbered from 0 to 7. Magazine 0 contains the pages shown with page number 800. Each magazines can contain 256 pages, numbered from 0x00 to 0xFF. Each page can have sub pages. Teletext data is transmitted line by line(packet). Most lines belong to a specific page, but some belong to a magazine, or just to the entire service.

teletext line 30 designation code 0
Lines with packet address 30 and 31 belong to the service. Line 30, designation code 0 identifies the initial teletext page, and identifies the station. It also contains the actual time for PDC.

teletext line 30 designation code 2
Line 30, designation code 2 identifies the initial teletext page, and identifies the current program for PDC. Lines with packet No 31 are used for private data broadcasting.


teletext line 29 This is some of the data for magazine 1. First is the line 29, which contains magazine related page enhancement data. It defines the background color for this magazine, to be used for level 2.5 decoders.

Page

teletext page level 2.5
When in the tree a page (or sub page) is selected a preview of that page is shown in the right panel. Teletext level 2.5 is (partially) supported in the preview.


This picture shows page 100, sub page 2. Notice the teletext block graphics are not supported in the tree view (left side). Every visible line can be expanded to see the actual data.

Apart from the normal visible lines this page has two other lines, line 26 is used for special characters (it puts the è in carrière on line 14), line 27 specifies the destinations for the colored buttons at the bottom of the page.

teletext page 100 subpage 2

teletext sub titles


For teletext based subtitles all subtitles are shown in the order they were transmitted. So it is possible to browse through the history of sub titles. This can be usefull to compare them with DVB based titles.

VPS / WSS

vps wss
This sample from the german DVB-T service of ARD shows a separate PID, which contains both VPS and WSS information.

DVB Subtitles

This segment has the same structure as that of teletext/EBU data. First there is a section showing the PES-packets (the "RAW"-data). When a PES packet contains enough information for a complete Display Set a preview of the title will be shown on the right. The seconds section "Titles" shows complete "Display Sets", even when they span multiple PES-packets. Also for Display Sets of type "page update" it will show the complete title, also using segments defined in earlier Display Sets. (This mechanism is often used for subtitling live programs, where separate words are sent as an update to the title already on display.)

dvb subtitling ZDF
This picture shows a segment of a DVB subtitling stream of ZDF. Expanded is the section which defines the color pallette to be used for subtitling. On the right a preview of what the selected title looks like. The background picture here is just a place holder, not part of the actual video. It is there to give an impression of the readability and transparancy of the title.

MPEG2 Video background

When possible DVB Inspector will try to show the actual video image as background for the title. For this the following conditions have to be statisfied;

  • The titles are part of a service with MPEG2 Video
  • The MPEG2 video is available (not encrypted)
  • The stream with the MPEG2 video has previously been parsed

When all these conditions have been met DVB Inspector will for each title find the closest I-Frame (based on the PTS).

BBC subtitling with actual video background

TTML Subtitles

Timed Text Markup Language (TTML) subtitles are sent as XML documents. DVB inspector does not support a preview of what the subtitle will look like, however it can show the XML structure with color coding in the detail window..

TTML Pes packet
The structure of the TTML PES packet.

When you select the XML field, the right window will show the XML;
XML Preview
This view shows the structure of the XML, however some items may be presented in a different order (like the attributes). The semantics should be the same.

T2MI

T2MI Signalling
T2MI is detected when the T2MIDescriptor is present in the PMT.

T2MI Packets
After parsing the PID the individual T2MI packets are first displayed in the order they appear in the PID.

Save PLPThen follows a section where each PLP is shown separately. Here also the option is available to save the contents of a PLP as new .ts file to disk.

This page was last modified on 28/06/2023